[ipxe-devel] unstable http downloads

[Gene Cumm]

On Fri, Nov 29, 2013 at 10:20 AM, Thomas Mieslinger <miesi at pc-h.de> wrote:
> Hi,
>
> I have VMware VMs running on E5-2650 iron, 10g connected. The VM I want to
> install has an emulated e1000 chip which fist runs the stock vmware PXE ROM,
> then pxelinux 4.03 and then finally ipxe.lkrn.

What VMware product?  Why not try a newer version of PXELINUX?  Where
did your pxelinux.0 binary come from?  Tried an ipxe.iso perhaps?

> The http Server is a centos 6.4 with apache httpd-2.2.15-29 serving files.
>
> Downloads initiated by ipxe a very unstable. Often the vmlinuz or initrd.img
> file downloads stuck at 43% or so.
>
> The http servers tcp tuning values (tcp_wmem et al.) are centos stock
> configuration.
>
> How can I debug http downloading? Are there any recommendations like "use
> cubic congestion control on server side"? Should I try to increase the
> compiled in tcp receive buffer?

As mentioned, a packet capture from a switchport mirror is best.
Otherwise, from the HTTP server.

-- 
-Gene